The present invention relates generally to a cooling system for internal combustion engines such as used in vehicles, and more specifically to an improved radiator and pump configuration for an aqueous reverse-flow cooling system of the type disclosed in my co-pending application Ser. No. 907,392.
One characteristic of a reverse-flow cooling system is that coolant enters the engine coolant chambers at a relatively high point, passes downwardly through the coolant chambers and exits the engine block at a low point. Moreover, the coolant pump must be attached to a low point on the outlet side of the radiator. This geometry creates a potential gas trap at the top of the radiator, which, is complicated by the fact that the pressure relief and vent for the system is located at a high point of a gas separator/condenser in order to purge the engine and cylinder head coolant chambers of accumulated noncondensible gases. Trace amounts of gas and/or coolant vapor pass through the system into the radiator due to excessive volumes of coolant vapor produced during periods of high load and/or ambient conditions. If such noncondensible gases and/or coolant vapor are allowed to accumulate in a high point of the radiator without a means for venting, coolant will be displaced from the radiator by the existence of the gas pocket and an equal volume of coolant will be forced out of the cooling system vent to atmosphere. Initially the result will be a loss of cooling capacity in the radiator causing a higher coolant operating temperature. As the displacement of coolant increases due to additional gases being trapped within the radiator, system failure may occur.
There also exists a need to establish a means to maintain the engine cooling chamber filled with coolant after the engine has been shut off and a significant portion of coolant has been lost from the system. If such coolant loss is experienced while the engine is running, and there is no coolant level control means for the coolant chambers, when the coolant level is lowered in the radiator and the engine is running, the coolant pump will continue to draw from the radiator, keeping the engine coolant chambers filled with coolant, and lowering the coolant level in the radiator but not in the coolant chambers. However, when the engine is turned-off, and the pump stops flowing coolant, the coolant level in the coolant chambers of the engine is immediately lowered and raised in the radiator as the effect of gravity reacts to equalize the two levels. Severe damage may occur from such losses since the head coolant chamber is at the highest heat level of the entire engine. Even at moderate loads and heat levels severe damage such as metal fatigue, cracking, and distortion will occur from such losses of coolant.